lib/trace-ir/clock-value.c

   1 /*
   2  * Copyright 2017-2018 Philippe Proulx <pproulx@efficios.com>
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a copy
   5  * of this software and associated documentation files (the "Software"), to deal
   6  * in the Software without restriction, including without limitation the rights
   7  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8  * copies of the Software, and to permit persons to whom the Software is
   9  * furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  17  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  18  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  19  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  20  * SOFTWARE.
  21  */
  22
  23 #define BT_LOG_TAG "CLOCK-VALUE"
  24 #include <babeltrace/lib-logging-internal.h>
  25
  26 #include <babeltrace/assert-pre-internal.h>
  27 #include <babeltrace/compat/uuid-internal.h>
  28 #include <babeltrace/trace-ir/clock-class-internal.h>
  29 #include <babeltrace/trace-ir/clock-value-internal.h>
  30 #include <babeltrace/compiler-internal.h>
  31 #include <babeltrace/types.h>
  32 #include <babeltrace/compat/string-internal.h>
  33 #include <inttypes.h>
  34 #include <babeltrace/object-internal.h>
  35 #include <babeltrace/assert-internal.h>
  36
  37 BT_HIDDEN
  38 void bt_clock_value_destroy(struct bt_clock_value *clock_value)
  39 {
  40         BT_LIB_LOGD("Destroying clock value: %!+k", clock_value);
  41         BT_OBJECT_PUT_REF_AND_RESET(clock_value->clock_class);
  42         g_free(clock_value);
  43 }
  44
  45 BT_HIDDEN
  46 struct bt_clock_value *bt_clock_value_new(struct bt_clock_class *clock_class)
  47 {
  48         struct bt_clock_value *ret = NULL;
  49
  50         BT_ASSERT(clock_class);
  51         BT_LIB_LOGD("Creating clock value object: %![cc-]+K=",
  52                 clock_class);
  53         ret = g_new0(struct bt_clock_value, 1);
  54         if (!ret) {
  55                 BT_LOGE_STR("Failed to allocate one clock value.");
  56                 goto end;
  57         }
  58
  59         bt_object_init_unique(&ret->base);
  60         ret->clock_class = clock_class;
  61         bt_object_get_no_null_check(clock_class);
  62         bt_clock_class_freeze(clock_class);
  63         BT_LIB_LOGD("Created clock value object: %!+k", ret);
  64
  65 end:
  66         return ret;
  67 }
  68
  69 BT_HIDDEN
  70 struct bt_clock_value *bt_clock_value_create(struct bt_clock_class *clock_class)
  71 {
  72         struct bt_clock_value *clock_value = NULL;
  73
  74         BT_ASSERT(clock_class);
  75         clock_value = bt_object_pool_create_object(&clock_class->cv_pool);
  76         if (!clock_value) {
  77                 BT_LIB_LOGE("Cannot allocate one clock value from clock class's clock value pool: "
  78                         "%![cc-]+K", clock_class);
  79                 goto error;
  80         }
  81
  82         if (likely(!clock_value->clock_class)) {
  83                 clock_value->clock_class = clock_class;
  84                 bt_object_get_no_null_check(clock_class);
  85         }
  86
  87         goto end;
  88
  89 error:
  90         if (clock_value) {
  91                 bt_clock_value_recycle(clock_value);
  92                 clock_value = NULL;
  93         }
  94
  95 end:
  96         return clock_value;
  97 }
  98
  99 BT_HIDDEN
 100 void bt_clock_value_recycle(struct bt_clock_value *clock_value)
 101 {
 102         struct bt_clock_class *clock_class;
 103
 104         BT_ASSERT(clock_value);
 105         BT_LIB_LOGD("Recycling clock value: %!+k", clock_value);
 106
 107         /*
 108          * Those are the important ordered steps:
 109          *
 110          * 1. Reset the clock value object, but do NOT put its clock
 111          *    class's reference. This clock class contains the pool to
 112          *    which we're about to recycle this clock value object, so
 113          *    we must guarantee its existence thanks to this existing
 114          *    reference.
 115          *
 116          * 2. Move the clock class reference to our `clock_class`
 117          *    variable so that we can set the clock value's clock class
 118          *    member to NULL before recycling it. We CANNOT do this
 119          *    after we put the clock class reference because this
 120          *    bt_object_put_ref() could destroy the clock class, also destroying
 121          *    its clock value pool, thus also destroying our clock value
 122          *    object (this would result in an invalid write access).
 123          *
 124          * 3. Recycle the clock value object.
 125          *
 126          * 4. Put our clock class reference.
 127          */
 128         bt_clock_value_reset(clock_value);
 129         clock_class = clock_value->clock_class;
 130         BT_ASSERT(clock_class);
 131         clock_value->clock_class = NULL;
 132         bt_object_pool_recycle_object(&clock_class->cv_pool, clock_value);
 133         bt_object_put_ref(clock_class);
 134 }
 135
 136 uint64_t bt_clock_value_get_value(const struct bt_clock_value *clock_value)
 137 {
 138         BT_ASSERT_PRE_NON_NULL(clock_value, "Clock value");
 139         BT_ASSERT_PRE(clock_value->is_set,
 140                 "Clock value is not set: %!+k", clock_value);
 141         return clock_value->value_cycles;
 142 }
 143
 144 int bt_clock_value_get_ns_from_origin(const struct bt_clock_value *clock_value,
 145                 int64_t *ret_value_ns)
 146 {
 147         int ret = 0;
 148         BT_ASSERT_PRE_NON_NULL(clock_value, "Clock value");
 149         BT_ASSERT_PRE_NON_NULL(ret_value_ns, "Value (ns) (output)");
 150         BT_ASSERT_PRE(clock_value->is_set,
 151                 "Clock value is not set: %!+k", clock_value);
 152
 153         if (clock_value->ns_from_origin_overflows) {
 154                 BT_LIB_LOGD("Clock value, once converted to nanoseconds from origin, "
 155                         "overflows the signed 64-bit integer range: "
 156                         "%![cv-]+k", clock_value);
 157                 ret = -1;
 158                 goto end;
 159         }
 160
 161         *ret_value_ns = clock_value->ns_from_origin;
 162
 163 end:
 164         return ret;
 165 }
 166
 167 const struct bt_clock_class *bt_clock_value_borrow_clock_class_const(
 168                 const struct bt_clock_value *clock_value)
 169 {
 170         BT_ASSERT_PRE_NON_NULL(clock_value, "Clock value");
 171         return clock_value->clock_class;
 172 }